There is an ongoing concern in the tobacco industry to produce cigarettes having wrappers which reduce the ignition proclivity of the smoking article, or the tendency of the smoking article to ignite surfaces which come into contact with the lit smoking article. Reports have been made of fires attributed to burning cigarettes coming into contact with combustible materials. A justifiable interest exists in the industry to reduce the tendency of cigarettes, or other smoking articles to ignite surfaces and materials used in furniture, bedding, and the like upon contact.
Thus, a desirable feature of smoking articles, particularly cigarettes, is that they self-extinguish upon being dropped or left in a free burning state in contact with combustible materials.
It has long been recognized in the tobacco industry that the cigarette wrapper has a significant influence on the smolder characteristics of the cigarette. In this regard, various attempts have been made in the art to alter or modify the cigarette wrappers in order to achieve the desired tendency of the cigarette to self-extinguish, or in other words to reduce the ignition proclivity characteristics of cigarettes.
The prior art describes the application of film-forming solutions to cigarette paper to reduce the paper permeability and control the burn rate. It has been shown that when these materials have been applied in discrete areas along the length of the cigarette, the cigarette shows a reduced propensity to ignite a substrate, and tends to self-extinguish.
U.S. Pat. No. 5,878,753 to Peterson and U.S. Pat. No. 5,820,998 to Hotaling, et al, which are incorporated herein by reference, for example, describe a smoking article wrapper being treated with a film-forming aqueous solution to reduce permeability. U.S. Pat. No. 5,878,754 to Peterson which is also incorporated herein by reference describes a smoking article wrapper being treated with a non-aqueous solution of a solvent soluble polymer dissolved in a non-aqueous solution to reduce permeability.
The present application is directed to further improvements in producing a wrapper for a smoking article with reduced ignition proclivity properties. In particular, the present disclosure is directed to improved formulations that may be applied to the paper wrapper.